The 1H8PWSR monoclonal antibody reacts with mouse interleukin(IL)-22. IL-22 is a 20kDa member of the IL-10 cytokine family that is secreted primarily by Th17, NK cells, and some other T cells. In in vitro Th17 cultures, induction of IL-22 expression is greater in response to IL-23 than IL-6 or TGF-ß, suggesting that this cytokine may be secreted by more fully differentiated Th17 cells in vivo. A heterodimer consisting of IL-10R2 and IL-22R1 serves as the receptor for IL-22. Th17-secreted IL-22 binds to the IL-22 receptor complexon target cells to induce the expression of anti-microbial peptides ß-defensin-2 and ß-defensin-3. Recently, it was demonstrated that IL-22 is able to protect hosts against bacterial infections of the lungs and gut.